Means of heating inclosures electrically



c. L. BURGHER July 30, 1929. Re. 17,386

- mums 0F HEATING INCLOSURES ELECTRICALLY Original Filed Oct. 27, 1925 INVENTOR Reimi d July 30, 1929.

UNITED STATES PATENT OFFICE.

CLAIR.EIEI'CIE'I L. BURGHEB, 01 NEW YORK, N; Y-

MEANS OF HEATING INCLOSURIES ELECTRICALLY.

Original 11'... 1,eso,21s, dated My invention relates to electric heaters of the class in which a heat conducting tube,

inclosing an electrical heating element electrically insulated therefrom but in heat conducting relation thereto, is provided with a longitudinal. series of vertically arranged transverse radiating plates in heat conducting contact with the tubeto transfer the heat from the resistant of the heating element to the vertical sections of air between the plates.

My invention consists'primarily in prolonging the plates vertically from the tube.

a length relatively great compared tothe width of the plates so as to form heated and unimpeded vertical air ducts, into the lower ends and open sides of which the cool air ward, so as to accelerate the circulation of the heated air columns upward from the ducts 2 and throughout the room or inclosure to be heated, substantially as hereinafter more fully set forth. a

In order that my invention may be fully understood, I shall first describe in detail the invention into practice andthen particularly point out the invention in the claim.

Reference is to be had to the accompanying drawings forming part of this application in which like parts are-designated by the same numbers in all the figures.

Figure 1 is a longitudinal sectional elevation of an electric heater embodying my invention.

Figure 2 is a cross-sectional elevation of the same on the line 2-2, Figure 1.

Figures 3 and 4 are detail views of parts of the electric heating element used in this embodiment of my invention. Q

Figure 5 is a detail view of one of the end bases of the same.

In the particular embodiment of my inven-.

mode in which I at present prefer to carry the February 21, 1928, Serial m. 65,106, filed October 27, 1925. Application for reissue filed Kay 21, 1929. Serial No. 366,074. i

efiicient and suitable character. In the present illustration of my invention, the heatin element consists of a bar 9 of electric insuating and heat insulating material, such for example as clay or a compound thereof, having a'longi'tudinal groove 14 along its upper side, ,in'" which is seated a resistant holder 10 consisting of a flat bar 12 of electric insulating but heat conducting material, such as, for example, alundum or asbestos, around which is wrapped, in this example, lengthwise, the coil of resistant wire 13 connectedto the source of electricit This wire I, at present, prefer to make 0 nickel chromium. 1

The resistant holder 10 is by preference covered on top by a sheet 10 of electric i-nsulating but heat conducting material, such as, for example, asbestos or alundum, no thicker than necessary to prevent escape of electricity from the resistant wire 13 to the tube 8.

p In the present illustration of my invention I have shown the upper and inner surface of the tube 8, as well as the upper surface of the resistant bar 9 and resistant holder 10 flattened to bring the heated resistant wire and its holder 10 as closely in contact as possi' ble with the upper wall of the tube 8 and relatively remote from the lower wall of the tube 8 so as to transfer as much as possible of the heat to the upper wall of the tube 8.- This unnecessary waste of heat downward is also avoided in this illustration by the relatively greater thickness of the heat insulating bar 9 below the resistant wire 13.

On the horizontal tube 8 is fixed in close heat conducting relation thereto, and, in this example of my invention, formed integrally a horizontal series of vertical air ducts whose walls formed by the plates 6 receive the heat b convection directly from the tube 8 and the electric heating element inclosed therein and in heat conducting contact therewith.

I at present prefer to make the plates or duct wallsG of aluminum, but they may be made of any other good heat conducting metal or material, and althoughshown in this example as formed integrally with the tube, they may bemade'separately and fixed thereon by swaging or by any other approved methodso as to bring them into intimate heat conducting relation thereto.

The plates 8 are here shown straight in herizontal cross section, which form is preferred,

butit is evident that the ducts may be made of anyother'form in" section appropriate to their effective functioning as herein set forth.

As hereinbefore briefly'descrihed, the cool air drawn into the lower ends and open sides of the vertical ducts is divided by the walls formed by the plates 6 into a longitudinal series of relatively thin vertical columns of air, which, as they ascend between the heated walls of the vertical ducts, are confined therebctwcen and progressively heated by the prolonged contact on both sides'therewith, and

their ascent thus continuously and progressively accelerated. The-result 1s that, lnstead j of a relatively'statlonary or slowly rising and 8 horizontal asshown and the duct-forming plates rising therefrom as shown for reasons of effectiveness and convenience it is evident that the tube may be arranged at ,any inclination with respect to the horizontal and the vertical duct-forming plates may either rise or fall or both rise and fall vertically therefrom without changing the relative functions of the tubeand plates, and other mechanically equivalent variations in construction may be made in the actual practice of my invention without departing from the boundaries thereof as set forth in the following claim:

. I claim as my invention:

An electric heater comprising a heat conducting tube, an electric heating element extending through and in heat conducting relation to the tube, but electrically insulated therefrom, and a longitudinal series of vertical heat conducting plates fixed'to the tube in heat conducting relation thereto, said plates being substantially free of intervening obstructions and of a length relatively great compared to their width, and forming a longitudinal series of heated vertical air ducts.

In testimony whereof I afiix my signature.

CLARENCE L. BURGHER; 

